Research on the Execution Time Analysis Technology of the Worst Case System in Real Time System

Methods for handling process underruns and overruns when scheduling a set of real-time processes increase both system utilization and robustness in the presence of inaccurate estimates of the worst-case computations of real-time processes. In this paper, we present a method that efficiently re-computes latest start times for real time processes during run-time in the event that a real-time process is preempted or has completed (or overrun). The method effectively identifies which process latest start times will be affected by the preemption or completion of a process. Hence the method is able to effectively reduce real-time system overhead by selectively re-computing latest start times for the specific processes whose latest start times are changed by a process preemption or completion, as opposed to indiscriminately re-computing latest start times for all the processes.

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Dynamic Partitioned Cache Memory for Real-Time MPSoCs with Mixed Criticality

Journal of Circuits System and Computers ◽

10.1142/s0218126616500626 ◽

2016 ◽

Vol 25 (06) ◽

pp. 1650062 ◽

Cited By ~ 1

Author(s):

Gang Chen ◽

Kai Huang ◽

Long Cheng ◽

Biao Hu ◽

Alois Knoll

Keyword(s):

Real Time ◽

Cache Memory ◽

Time System ◽

Worst Case ◽

Real Time System ◽

Average Performance ◽

Shared Cache ◽

Worst Case Execution Time ◽

The One ◽

Major Factors

Shared cache interference in multi-core architectures has been recognized as one of major factors that degrade predictability of a mixed-critical real-time system. Due to the unpredictable cache interference, the behavior of shared cache is hard to predict and analyze statically in multi-core architectures executing mixed-critical tasks, which will not only result in difficulty of estimating the worst-case execution time (WCET) but also introduce significant worst-case timing penalties for critical tasks. Therefore, cache management in mixed-critical multi-core systems has become a challenging task. In this paper, we present a dynamic partitioned cache memory for mixed-critical real-time multi-core systems. In this architecture, critical tasks can dynamically allocate and release the cache resourse during the execution interval according to the real-time workload. This dynamic partitioned cache can, on the one hand, provide the predicable cache performance for critical tasks. On the other hand, the released cache can be dynamically used by non-critical tasks to improve their average performance. We demonstrate and prototype our system design on the embedded FPGA platform. Measurements from the prototype clearly demonstrate the benefits of the dynamic partitioned cache for mixed-critical real-time multi-core systems.

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PBench: A Parallel, Real-Time Benchmark Suite

Academic Perspective Procedia ◽

10.33793/acperpro.01.01.37 ◽

2018 ◽

Vol 1 (1) ◽

pp. 178-186 ◽

Cited By ~ 1

Author(s):

Sevil Serttaş ◽

Veysel Harun Şahin

Keyword(s):

Real Time ◽

Execution Time ◽

Matrix Multiplication ◽

Multiprocessor Systems ◽

Time Analysis ◽

Worst Case ◽

Analysis Methods ◽

Worst Case Execution Time ◽

Benchmark Suite ◽

Time Systems

Real-time systems are widely used from the automotive industry to the aerospace industry. The scientists, researchers, and engineers who develop real-time platforms, worst-case execution time analysis methods and tools need to compare their solutions to alternatives. For this purpose, they use benchmark applications. Today many of our computing systems are multicore and/or multiprocessor systems. Therefore, to be able to compare the effectiveness of real-time platforms, worst-case execution time analysis methods and tools, the research community need multi-threaded benchmark applications which scale on multicore and/or multiprocessor systems. In this paper, we present the first version of PBench, a parallel, real-time benchmark suite. PBench includes different types of multi-threaded applications which implement various algorithms from searching to sorting, matrix multiplication to probability distribution calculation. In addition, PBench provides single-threaded versions of all programs to allow side by side comparisons.

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Static properties of commercial embedded real-time programs, and their implication for worst-case execution time analysis

Proceedings of the Fifth IEEE Real-Time Technology and Applications Symposium ◽

10.1109/rttas.1999.777660 ◽

2003 ◽

Cited By ~ 14

Author(s):

J. Engblom

Keyword(s):

Real Time ◽

Execution Time ◽

Time Analysis ◽

Static Properties ◽

Worst Case ◽

Worst Case Execution Time

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